The present invention relates to fastening devices for fastening a plurality of members together, and particularly to a blind rivet which enables a plurality of members to be fastened together where access is available only from one side of the members.
The conventional blind rivet comprises a tubular shell formed with an enlarged head at one end and a shank at its opposite end, and a mandrel formed with a stem at one end and an enlarged head at its opposite end. The shell and mandrel are insertable from one side of a plurality of members to be fastened together through aligned openings in the members, with the shell head engaging the one side of the members and with the mandrel head engaging the end of the shell shank at the opposite side of the members. The construction is such that a pull force applied to the mandrel from the one side of the members in the direction to axially compress the shell shank by the mandrel head, causes the shell shank to bulge outwardly, and thereby to securely fasten the plurality of members between the shell head and the bulged portion of the shell shank. Examples of such known blind rivet constructions are described in U.S. Pat. Nos. 2,030,167, 2,030,168, 2,030,169, 2,061,628, 3,149,530, 3,286,580, 3,414,965, 3,515,028, 4,189,977, 4,222,304 and 4,639,174.
An object of the present invention is to provide a blind rivet of the foregoing type having an improved gripping action between the mandrel and the shell. Another object of the invention is to provide a blind rivet of a relatively simple construction which can be produced in volume and at low cost.